Before restarting the heating you must proceed to purge the radiators. This simple operation eliminates the air pockets enclosed in the central heating system and improves the operation of the same. We will tell you that how to bleed a radiator the right way.

Why to bleed a radiator the right way?

In residential buildings with communal boiler rooms, in winter the heat reaches the homes thanks to the central heating radiators, which are responsible for moving the heat produced by the boiler to the houses. These elements of the heating system are already part of the decoration of thousands of homes. To work perfectly, it is convenient to purge the radiators before the heating season begins.

What is the meaning of the bleed a radiator the right way?

During the months in which the radiators have remained inactive, it is common that works or other actions have been carried out in the heating installation. To carry out these actions, the water heating circuit must be emptied and, once finished; the corresponding filling must be carried out again. In this process of water filling the installation, air pockets are created that go to the central heating radiators. This air must be expelled through the purge. To do this, simply turn the purge valve and wait for the water to come out, indicating that the air has been expelled completely.

A good trick to not dirty the room is to place a plastic bottle under the valve so that the water falls into it. If a hole of about 10 mm in diameter is made in the upper part of the bottle near the neck of the bottle, the valve can be manipulated with a screwdriver while all the liquid remains inside the container.

When to bleed a radiator the right way?

It is advisable to purge before the heating season begins. And it should always be done with the cold radiator since doing it hot can cause burns. However, if even with the boiler at full capacity the user notices that the radiator does not heat adequately, perhaps the purging has not been carried out correctly and has to be repeated. In the case of radiators that are part of central heating installations, it is essential that those users who will purge radiators from their homes notify the person responsible for the installation. This way they can find out if the heating system has been filled or if it is still empty, in which case it would be useless to purge it because there is no water in the installation.

And, if the filling has taken place, the person in charge of the installation will be on notice and will be able to ensure that, in spite of the purges, the pressure level of the central heating system remains constant. This prevents malfunctioning in the entire installation.

Bleed a radiator the right way: cut the water supply

The purge of a radiator is necessary when we realize that it does not heat up or does it only in its lower part, or you can hear bubbling noises inside it. If a radiator does not heat its lower part at least, the problem will not be solved with a purge, it can happen that the radiator shut-off valve is closed, or that there is a problem of water circulation, in this case, it would be necessary to call a boiler specialist. The most recent installations, for 30 years, are equipped with an air purge, often automatic, installed directly in the boiler. Many radiators also have automatic vents that do not require intervention. It is advisable to start at the beginning of the circuit, that is, by the radiator closest to the boiler, and finish by the furthest, especially in multi-story houses. However, with the passage of time, you will learn to know your installation, which will facilitate the purge. In effect, the air almost always accumulates in the same places of the heating circuit.

How bleed a radiator the right way works?

The central heating must be stopped. This means that the circulation pump of the boiler is not working. The simplest thing is to place the boiler in the summer position. Ideally, wait for the radiators to cool down. Otherwise, we must operate carefully so as not to burn ourselves. The purge screw is located on the top of the radiator, which is where the air accumulates. Depending on the model, it is a flat head screw or a hexagonal head bolt. Bleed a radiator the right way helps.

Bleed a radiator the right way : expel the air

We will place a container under the purge screw. If the radiator is not cold it is better not to use a glass container as it could explode in your hands causing deep cuts. Loosen the screw a quarter of a turn and then continue to open it very slowly until you hear a whistle that is the air that escapes. After a few moments water will start to flow out, let the purge continue for a couple more seconds and then close the purge screw without forcing it. If you notice that it continues to leak and you have to force the screw to stop it, think about changing the purge valve.

Purge the radiators: reestablish the pressure

After the purge of the radiators, the water pressure of the heating circuit decreases. It is then necessary to re-establish it by adding more water pressure to the circuit. The filling tap is located near the boiler. You must open it with caution and watch the pressure gauge of the boiler panel; you must close the tap when the pressure reaches:

> 1 to 1.5 bars for a house with one floor or apartment.

> 1.8 to 2 bars for a multi-story house.

If you have to perform this operation several times during the same winter, suspect that there may be a leak somewhere.

Automatic drain for radiators

It is possible to install automatic purgers in the heating circuit, which will avoid doing it by hand. The automatic drain consists of a float that closes a small hole located in its upper part:

  • When all is well, the water present in the radiator keeps the float in high position, the hole is then covered.
  • In the presence of air, it rises towards the trap, the volume of the water drops, leaving the orifice open: air escapes outside the radiator.
  • It is advisable to install an automatic drain near the boiler and at the last of the radiators in the circuit.

Bleed a radiator the right way- verify its proper functioning:

  • Unscrew the automatic drain plug.
  • With the help of a toothpick, we rest on the small hole to move the valve.
  • If the water comes out immediately, the trap is working correctly (be careful if the radiator is hot since the water will be very hot).